The congresswoman, who was shot in the head at an event outside a Tucson grocery store on Jan. 8, made the request to hospital workers who delivered her meal on Monday at TIRR Memorial Hermann, the Houston rehab center where she is receiving occupational therapy.

Giffords spoke for the first time a few days ago and continues to talk "more and more," said C.J. Karamargin, a Giffords spokesman.

"I think this is significant, as it tells us that congresswoman Giffords is able to speak and is able to have an opinion of what she wants to eat. It shows that she has initiation of original thought and is able to convey her wishes," Williams said. "I think this is a good sign that she is able to appropriately express herself. Appropriate expression is not always the case after a head injury. I think we could call this major progress in her recovery."

But Dr. John Whyte from the Moss Rehabilitation Research Institute cautioned that "the pace of change is more informative than the status on a single day."

"The bottom line is that rather few patients even with significant language impairment are incapable of saying anything at all," Whyte said. "So it's the complexity, length, grammatical structure and fluency of language that are most informative."

In a Facebook post Tuesday, the one-month anniversary of the tragedy, Giffords' husband, astronaut Mark Kelly, thanked everyone for their support and gave an update on Giffords' progress.

"It is hard to believe that only one month has passed since Gabrielle was shot. The doctors say she is recovering at lightning speed considering her injury but they aren't kidding when they say this is a marathon process," Kelly wrote. "There are encouraging signs everyday though. Gabby's appetite is back and -- even though it's hospital food -- she's enjoying three meals a day."

Apparently, Giffords now is able to have a say in her meals. Giffords' words came just days after her husband announced his plan to go ahead and return to space in April.

"I ultimately made the decision that I would like to return and command STS-134," Kelly said at a press conference at the Johnson Space Center in Houston Friday. "I absolutely thought this was the right thing for me to do."

Kelly said the decision to leave his wife's side to fly the space shuttle Endeavour on its final mission was something Giffords would support.

"I know her very well and she would be very comfortable with the decision that I made," Kelly said.

Mark Kelly and Gabrielle Giffords

Kelly is scheduled to lift off from the Kennedy Space Center Florida on April 19. He will command a crew of six astronauts, delivering the last major component to the International Space Station. He said he believes Giffords will be able to see Endeavour go.

"I have every intention that she'll be there for launch. I've talked to her doctors about that," he said.

Kelly has been with Giffords for every step of her month-long recovery. She was nearly killed when she was shot in the head during a rampage in front of a Tucson grocery store on Jan. 8. Kelly was faced with a difficult choice -- stay with her, or resume training for the flight, possibly his last chance ever to fly in space.

Last month, Kelly told ABC News' Diane Sawyer, "Ideally I would like to have that conversation with Gabby. I've flown in space three times. I don't have to do it again. My number-one goal is to make sure that my crew is safe and that they can execute this mission safely."

After the Tucson shooting, NASA, at Kelly's request, appointed a backup commander to train with the STS-134 crew. Rick Sturckow, a retired Marine Colonel, has flown four missions into space, and would have commanded the flight in Kelly's absence.

Prior to the announcement, Chief Astronaut Peggy Whitson told ABC News, "Obviously, Mark has trained with this crew for over a year and so he is the ideal person for this crew from a mission risk perspective. It reduces our mission risk from that perspective, if we feel he is ready to go and would be undistracted by the circumstances then we will decide on that. But he, he is a tough guy, as you have seen. He's got his stuff together."

"Our job was to evaluate what was best for the mission," said Brent Jett, director of NASA flight crew operations. "We felt we covered all those areas to assess that."

Kelly and his crew have trained for a year and a half for the mission, so it won't take much for him to get back into the routine, and the Johnson Space Center is close enough to the hospital that he can see his wife often. His parents live in Houston, and Giffords' mother Gloria is also in Houston, so she is surrounded by family and friends.

Kelly's twin brother, Scott, is currently in orbit on the space station. The brothers had hoped to meet in space, but timing was not on their side -- Mark's mission was pushed back to April 19, and Scott returns to Earth in March.

In an interview from space, Scott Kelly told The Associated Press his brother is doing as well as anyone could expect. "His wife, the wounded congresswoman, is improving every day in rehab in Houston. He's concentrating on Gabby's care, but he's also been going back to work."

Mark Kelly's decision to go ahead with the April mission will force him to train rigorously, and then be gone from home for about a month. Astronauts go into quarantine about two weeks before flight, to protect against illnesses breaking out in orbit, where even a head cold can be debilitating.

Crews usually leave Houston for the Kennedy Space Center about five days before launch. The flight itself is currently planned to run 14 days, though shuttle landings are often delayed by weather. Some astronauts return to Houston the day they land, though many need a day or two to readapt to the Earth's gravity.

Dr. John Holcomb, the trauma surgeon heading Giffords' team at Memorial Hermann Hospital in Houston, said he was confident that Kelly would make the right decision for his family.

"I think that there's a certain amount of settling into a routine that happens once you're out of the ICU," Holcomb said, "and I think Capt. Kelly will get into a routine that he's comfortable with, that his wife's comfortable with, and that's obviously a very personal decision."